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Refactor and documentation

patch-2
Yemel Jardi 10 years ago
parent
commit
8eca7285e0
  1. 412
      lib/transport/message.js
  2. 133
      lib/transport/peer2.js

412
lib/transport/message.js

@ -1,62 +1,175 @@
'use strict';
var Buffers = require('buffers');
var buffertools = require('buffertools');
var Put = require('bufferput');
var util = require('util');
var Block = require('../block');
var BufferReader = require('../encoding/bufferreader');
var BufferUtil = require('../util/buffer');
var Hash = require('../crypto/hash');
var Random = require('../crypto/random');
var CONNECTION_NONCE = Random.getPseudoRandomBuffer(8);
var PROTOCOL_VERSION = 70000;
var MESSAGES = {
'version' : Version,
'verack': VerAck,
'inv': Inventory,
'ping': Ping,
'pong': Pong,
'addr': Addresses,
'getaddr': GetAddresses,
'reject': Reject
/**
* Static helper for consuming a data buffer until the next message.
*
* @param{Network} network - the network object
* @param{Buffer} dataBuffer - the buffer to read from
* @returns{Message|undefined} A message or undefined if there is nothing to read.
*/
var parseMessage = function(network, dataBuffer) {
if (dataBuffer.length < 20) return;
// Search the next magic number
if (!discardUntilNextMessage(network, dataBuffer)) return;
var PAYLOAD_START = 16;
var payloadLen = (dataBuffer.get(PAYLOAD_START)) +
(dataBuffer.get(PAYLOAD_START + 1) << 8) +
(dataBuffer.get(PAYLOAD_START + 2) << 16) +
(dataBuffer.get(PAYLOAD_START + 3) << 24);
var messageLength = 24 + payloadLen;
if (dataBuffer.length < messageLength) return;
var command = dataBuffer.slice(4, 16).toString('ascii').replace(/\0+$/, '');
var payload = dataBuffer.slice(24, messageLength);
var checksum = dataBuffer.slice(20, 24);
var checksumConfirm = Hash.sha256sha256(payload).slice(0, 4);
if (buffertools.compare(checksumConfirm, checksum) !== 0) {
dataBuffer.skip(messageLength);
return;
}
dataBuffer.skip(messageLength);
return Message.buildMessage(command, payload);
};
module.exports.parseMessage = parseMessage;
/**
* Internal function that discards data until founds the next message.
*/
function discardUntilNextMessage(network, dataBuffer) {
var magicNumber = network.networkMagic;
var i = 0;
for (;;) {
// check if it's the beginning of a new message
var packageNumber = dataBuffer.slice(0, 4);
if (buffertools.compare(packageNumber, magicNumber) == 0) {
dataBuffer.skip(i);
return true;
}
// did we reach the end of the buffer?
if (i > (dataBuffer.length - 4)) {
dataBuffer.skip(i);
return false;
}
i++; // continue scanning
}
}
module.exports.buildMessage = function(command, payload) {
var Message = MESSAGES[command];
/**
* Abstract Message that knows how to parse and serialize itself.
* Concret subclases should implement {fromBuffer} and {getPayload} methods.
*/
function Message() {};
Message.COMMANDS = {};
Message.buildMessage = function(command, payload) {
try {
console.log('Message Class', Message);
return new Message().fromBuffer(payload);
var CommandClass = Message.COMMANDS[command];
return new CommandClass().fromBuffer(payload);
} catch (err) {
console.log('Error while parrsing message', command);
console.log(err);
console.log('Error while parsing message', err);
throw err;
}
};
/**
* Parse instance state from buffer.
*
* @param{Buffer} payload - the buffer to read from
* @returns{Message} The same message instance
*/
Message.prototype.fromBuffer = function(payload) {
return this;
};
/**
* Serialize the payload into a buffer.
*
* @returns{Buffer} the serialized payload
*/
Message.prototype.getPayload = function() {
return BufferUtil.EMPTY_BUFFER;
};
/**
* Serialize the message into a buffer.
*
* @returns{Buffer} the serialized message
*/
Message.prototype.serialize = function(network) {
var magic = network.networkMagic;
var commandBuf = new Buffer(this.command, 'ascii');
if (commandBuf.length > 12) throw 'Command name too long';
var payload = this.getPayload();
var checksum = Hash.sha256sha256(payload).slice(0, 4);
// -- HEADER --
var message = new Put();
message.put(magic);
message.put(commandBuf);
message.pad(12 - commandBuf.length); // zero-padded
message.word32le(payload.length);
message.put(checksum);
// -- BODY --
message.put(payload);
return message.buffer();
}
// ====== VERSION MESSAGE ======
/**
* Version Message
*
* @param{string} subversion - version of the client
* @param{Buffer} nonce - a random 8 bytes buffer
*/
function Version(subversion, nonce) {
this.command = 'version';
this.version = PROTOCOL_VERSION;
this.subversion = subversion || '/BitcoinX:0.1/';
this.nonce = nonce || CONNECTION_NONCE;
};
util.inherits(Version, Message);
Version.prototype.fromBuffer = function(payload) {
var message = new Version();
var parser = new BufferReader(payload);
message.version = parser.readUInt32LE();
message.services = parser.readUInt64LEBN();
message.timestamp = parser.readUInt64LEBN();
message.addr_me = parser.read(26);
message.addr_you = parser.read(26);
message.nonce = parser.read(8);
message.subversion = parser.readVarintBuf();
message.start_height = parser.readUInt32LE();
return message;
this.version = parser.readUInt32LE();
this.services = parser.readUInt64LEBN();
this.timestamp = parser.readUInt64LEBN();
this.addr_me = parser.read(26);
this.addr_you = parser.read(26);
this.nonce = parser.read(8);
this.subversion = parser.readVarintBuf();
this.start_height = parser.readUInt32LE();
return this;
};
Version.prototype.serialize = function() {
Version.prototype.getPayload = function() {
var put = new Put();
put.word32le(this.version); // version
put.word64le(1); // services
@ -71,30 +184,33 @@ Version.prototype.serialize = function() {
return put.buffer();
};
module.exports.Version = Version;
module.exports.Version = Message.COMMANDS['version'] = Version;
// ====== INV MESSAGE ======
/**
* Inv Message
*
* @param{Array} inventory - reported elements
*/
function Inventory(inventory) {
this.command = 'inv';
this.inventory = inventory || [];
}
util.inherits(Inventory, Message);
Inventory.prototype.fromBuffer = function(payload) {
var message = new Inventory();
var parser = new BufferReader(payload);
var count = parser.readVarintNum();
for (var i = 0; i < count; i++) {
message.inventory.push({
this.inventory.push({
type: parser.readUInt32LE(),
hash: parser.read(32)
});
}
return message;
return this;
};
Inventory.prototype.serialize = function() {
Inventory.prototype.getPayload = function() {
var put = new Put();
put.varint(this.inventory.length);
@ -106,9 +222,13 @@ Inventory.prototype.serialize = function() {
return put.buffer();
};
module.exports.Inventory = Inventory;
module.exports.Inventory = Message.COMMANDS['inv'] = Inventory;
// ====== GETDATA MESSAGE ======
/**
* Getdata Message
*
* @param{Array} inventory - requested elements
*/
function GetData(inventory) {
this.command = 'getdata';
this.inventory = inventory || [];
@ -117,24 +237,33 @@ function GetData(inventory) {
util.inherits(GetData, Inventory);
module.exports.GetData = GetData;
// ====== PING MESSAGE ======
/**
* Ping Message
*
* @param{Buffer} nonce - a random 8 bytes buffer
*/
function Ping(nonce) {
this.command = 'ping';
this.nonce = nonce || CONNECTION_NONCE;
}
util.inherits(Ping, Message);
Ping.prototype.fromBuffer = function(payload) {
var nonce = new BufferReader(payload).read(8);
return new Ping(nonce);
this.nonce = new BufferReader(payload).read(8);
return this;
};
Ping.prototype.serialize = function() {
Ping.prototype.getPayload = function() {
return this.nonce;
};
module.exports.Ping = Ping;
module.exports.Ping = Message.COMMANDS['ping'] = Ping;
// ====== PONG MESSAGE ======
/**
* Pong Message
*
* @param{Buffer} nonce - a random 8 bytes buffer
*/
function Pong(nonce) {
this.command = 'pong';
this.nonce = nonce || CONNECTION_NONCE;
@ -143,22 +272,25 @@ function Pong(nonce) {
util.inherits(Pong, Ping);
module.exports.Pong = Pong;
// ====== ADDR MESSAGE ======
function Addresses(nonce) {
/**
* Addr Message
*
* @param{Array} addresses - array of know addresses
*/
function Addresses(addresses) {
this.command = 'addr';
this.addresses = [];
this.addresses = addresses || [];
}
util.inherits(Addresses, Message);
Address.prototype.fromBuffer = function(payload) {
var message = new Address();
Addresses.prototype.fromBuffer = function(payload) {
var parser = new BufferReader(payload);
var addrCount = Math.min(parser.readVarintNum(), 1000);
message.addresses = [];
this.addresses = [];
for (var i = 0; i < addrCount; i++) {
// TODO: Time actually depends on the version of the other peer (>=31402)
message.addresses.push({
this.addresses.push({
time: parser.readUInt32LE(),
services: parser.readUInt64LEBN(),
ip: parser.read(16),
@ -166,167 +298,177 @@ Address.prototype.fromBuffer = function(payload) {
});
}
return message;
return this;
};
Address.prototype.serialize = function() {
Addresses.prototype.getPayload = function() {
return BufferUtil.EMPTY_BUFFER; // TODO
};
module.exports.Address = Address;
module.exports.Addresses = Message.COMMANDS['addr'] = Addresses;
// ====== GETADDR MESSAGE ======
/**
* GetAddr Message
*
*/
function GetAddresses() {
this.command = 'getaddr';
}
GetAddresses.prototype.fromBuffer = function() {
return new GetAddresses();
};
GetAddresses.prototype.serialize = function() {
return BufferUtil.EMPTY_BUFFER;
};
util.inherits(GetAddresses, Message);
module.exports.GetAddresses = Message.COMMANDS['getaddr'] = GetAddresses;
module.exports.GetAddresses = GetAddresses;
// ====== VERACK MESSAGE ======
/**
* Verack Message
*
*/
function VerAck() {
this.command = 'verack';
}
VerAck.prototype.fromBuffer = function() {
return new VerAck();
};
VerAck.prototype.serialize = function() {
return BufferUtil.EMPTY_BUFFER;
};
util.inherits(VerAck, Message);
module.exports.VerAck = Message.COMMANDS['verack'] = VerAck;
module.exports.VerAck = VerAck;
// ====== REJECT MESSAGE ======
// TODO: Parse REJECT message
/**
* Reject Message
*
*/
function Reject() {
this.command = 'reject';
}
util.inherits(Reject, Message);
Reject.prototype.fromBuffer = function() {
return new Reject();
};
Reject.prototype.serialize = function() {
return BufferUtil.EMPTY_BUFFER;
};
// TODO: Parse REJECT message
module.exports.Reject = Reject;
module.exports.Reject = Message.COMMANDS['reject'] = Reject;
// ====== ALERT MESSAGE ======
function Alert(payload) {
this.command = 'reject';
/**
* Alert Message
*
*/
function Alert() {
this.command = 'alert';
}
util.inherits(Alert, Message);
Alert.prototype.fromBuffer = function() {
var message = new Alert();
var parser = new BufferReader(payload);
message.payload = parser.readVarintBuf(); // TODO: Use current format
message.signature = parser.readVarintBuf();
return message;
this.payload = parser.readVarintBuf(); // TODO: Use current format
this.signature = parser.readVarintBuf();
return this;
};
Alert.prototype.serialize = function() {
Alert.prototype.getPayload = function() {
return BufferUtil.EMPTY_BUFFER; // TODO: Serialize
};
module.exports.Alert = Alert;
module.exports.Alert = Message.COMMANDS['alert'] = Alert;
// ====== HEADERS MESSAGE ======
/**
* Headers Message
*
* @param{Array} blockheaders - array of block headers
*/
function Headers(blockheaders) {
this.command = 'headers';
this.headers = blockheaders || [];
}
util.inherits(Headers, Message);
Headers.prototype.fromBuffer = function() {
var message = new Headers();
var parser = new BufferReader(payload);
var count = parser.readVarintNum();
message.headers = [];
this.headers = [];
for (i = 0; i < count; i++) {
var header = Block().fromBufferReader(parser);
message.headers.push(header);
this.headers.push(header);
}
return message;
return this;
};
Headers.prototype.serialize = function() {
Headers.prototype.getPayload = function() {
return BufferUtil.EMPTY_BUFFER; // TODO: Serialize
};
module.exports.Headers = Headers;
module.exports.Headers = Message.COMMANDS['headers'] = Headers;
// ====== BLOCK MESSAGE ======
/**
* Block Message
*
* @param{Block} block
*/
function Block(block) {
this.command = 'block';
this.block = block;
}
util.inherits(Block, Message);
Block.prototype.fromBuffer = function() {
var parser = new BufferReader(payload);
var block = Block().fromBufferReader(parser);
return new Block(block);
this.block = Block().fromBufferReader(parser);
return this;
};
Block.prototype.serialize = function() {
Block.prototype.getPayload = function() {
return BufferUtil.EMPTY_BUFFER; // TODO: Serialize
};
module.exports.Block = Block;
module.exports.Block = Message.COMMANDS['block'] = Block;
// ====== TX MESSAGE ======
/**
* Tx Message
*
* @param{Transaction} transaction
*/
function Transaction(transaction) {
this.command = 'tx';
this.transaction = transaction;
}
util.inherits(Transaction, Message);
Transaction.prototype.fromBuffer = function() {
var parser = new BufferReader(payload);
var transaction = Transaction().fromBufferReader(parser);
return new Transaction(transaction);
this.transaction = Transaction().fromBufferReader(parser);
return this;
};
Transaction.prototype.serialize = function() {
Transaction.prototype.getPayload = function() {
return BufferUtil.EMPTY_BUFFER; // TODO: Serialize
};
module.exports.Transaction = Transaction;
module.exports.Transaction = Message.COMMANDS['tx'] = Transaction;
// ====== GETBLOCKS MESSAGE ======
/**
* Getblocks Message
*
* @param{Array} starts - array of buffers with the starting block hashes
* @param{Buffer} [stop] - hash of the last block
*/
function GetBlocks(starts, stop) {
this.command = 'getblocks';
this.version = PROTOCOL_VERSION;
this.starts = starts || [];
this.stop = stop || BufferUtil.NULL_HASH;
}
util.inherits(GetBlocks, Message);
GetBlocks.prototype.fromBuffer = function() {
var message = new GetBlocks();
var parser = new BufferReader(payload);
message.version = parser.readUInt32LE();
this.version = parser.readUInt32LE();
var startCount = Math.min(parser.readVarintNum(), 500);
message.starts = [];
this.starts = [];
for (var i = 0; i < startCount; i++) {
message.starts.push(parser.read(32));
this.starts.push(parser.read(32));
}
message.stop = parser.read(32);
this.stop = parser.read(32);
return this;
};
GetBlocks.prototype.serialize = function() {
GetBlocks.prototype.getPayload = function() {
var put = new Put();
put.word32le(this.version);
put.varint(this.starts.length);
@ -346,9 +488,14 @@ GetBlocks.prototype.serialize = function() {
return put.buffer();
};
module.exports.GetBlocks = GetBlocks;
module.exports.GetBlocks = Message.COMMANDS['getblocks'] = GetBlocks;
// ====== GETHEADERS MESSAGE ======
/**
* Getheaders Message
*
* @param{Array} starts - array of buffers with the starting block hashes
* @param{Buffer} [stop] - hash of the last block
*/
function GetHeaders(starts, stop) {
this.command = 'getheaders';
this.version = PROTOCOL_VERSION;
@ -357,4 +504,21 @@ function GetHeaders(starts, stop) {
}
util.inherits(GetHeaders, GetBlocks);
module.exports.GetHeaders = GetHeaders;
module.exports.GetHeaders = Message.COMMANDS['getheaders'] = GetHeaders;
// TODO: Remove this PATCH (yemel)
Buffers.prototype.skip = function (i) {
if (i == 0) return;
if (i == this.length) {
this.buffers = [];
this.length = 0;
return;
}
var pos = this.pos(i);
this.buffers = this.buffers.slice(pos.buf);
this.buffers[0] = new Buffer(this.buffers[0].slice(pos.offset));
this.length -= i;
};

133
lib/transport/peer2.js

@ -1,16 +1,14 @@
'use strict';
var util = require('util');
var Buffers = require('buffers');
var EventEmitter = require('events').EventEmitter;
var Net = require('net');
var Put = require('bufferput');
var Buffers = require('buffers');
var buffertools = require('buffertools');
var Socks5Client = require('socks5-client');
var EventEmitter = require('events').EventEmitter;
var util = require('util');
var Networks = require('../networks');
var Hash = require('../crypto/hash');
var Message = require('./message');
var Messages = require('./message');
var MAX_RECEIVE_BUFFER = 10000000;
@ -143,114 +141,38 @@ Peer.prototype.disconnect = function() {
};
/**
* Internal function that tries to read a message from the data buffer
* Send a Message to the remote peer.
*/
Peer.prototype._readMessage = function() {
if (this.dataBuffer.length < 20) return;
var magic = this.network.networkMagic;
// Search the next magic number
if (!this._discardUntilNextMessage()) return;
var PAYLOAD_START = 16;
var payloadLen = (this.dataBuffer.get(PAYLOAD_START)) +
(this.dataBuffer.get(PAYLOAD_START + 1) << 8) +
(this.dataBuffer.get(PAYLOAD_START + 2) << 16) +
(this.dataBuffer.get(PAYLOAD_START + 3) << 24);
var messageLength = 24 + payloadLen;
if (this.dataBuffer.length < messageLength) return;
var command = this.dataBuffer.slice(4, 16).toString('ascii').replace(/\0+$/, '');
var payload = this.dataBuffer.slice(24, messageLength);
var checksum = this.dataBuffer.slice(20, 24);
var checksumConfirm = Hash.sha256sha256(payload).slice(0, 4);
if (buffertools.compare(checksumConfirm, checksum) !== 0) {
this.dataBuffer.skip(messageLength);
return;
}
console.log('we have a message:', command);
var message = Message.buildMessage(command, payload);
if (message) this.emit(command, message);
console.log('Emiting message', command, message);
this.dataBuffer.skip(messageLength);
this._readMessage();
Peer.prototype.sendMessage = function(message) {
this.socket.write(message.serialize(this.network));
};
/**
* Internal function that discards data until founds the next message.
*/
Peer.prototype._discardUntilNextMessage = function() {
var magicNumber = this.network.networkMagic;
var i = 0;
for (;;) {
// check if it's the beginning of a new message
var packageNumber = this.dataBuffer.slice(0, 4);
if (buffertools.compare(packageNumber, magicNumber) == 0) {
this.dataBuffer.skip(i);
return true;
}
// did we reach the end of the buffer?
if (i > (this.dataBuffer.length - 4)) {
this.dataBuffer.skip(i);
return false;
}
i++; // continue scanning
}
}
/**
* Internal function that sends VERSION message to the remote peer.
*/
Peer.prototype._sendVersion = function() {
var message = new Message.Version();
this._sendMessage(message.command, message.serialize());
};
/**
* Send a PING message to the remote peer.
*/
Peer.prototype.sendPing = function(nonce) {
var message = new Message.Pong(nonce);
this._sendMessage(message.command, message.serialize());
var message = new Messages.Version();
this.sendMessage(message);
};
/**
* Send a PONG message to the remote peer.
*/
Peer.prototype.sendPong = function(nonce) {
var message = new Message.Pong(nonce);
this._sendMessage(message.command, message.serialize());
Peer.prototype._sendPong = function(nonce) {
var message = new Messages.Pong(nonce);
this.sendMessage(message);
};
/**
* Internal function that sends a message to the remote peer.
* Internal function that tries to read a message from the data buffer
*/
Peer.prototype._sendMessage = function(command, payload) {
var magic = this.network.networkMagic;
var commandBuf = new Buffer(command, 'ascii');
if (commandBuf.length > 12) throw 'Command name too long';
var checksum = Hash.sha256sha256(payload).slice(0, 4);
// -- HEADER --
var message = new Put();
message.put(magic); // magic bytes
message.put(commandBuf); // command name
message.pad(12 - commandBuf.length); // zero-padded
message.word32le(payload.length); // payload length
message.put(checksum); // checksum
// -- BODY --
message.put(payload); // payload data
Peer.prototype._readMessage = function() {
var message = Messages.parseMessage(this.network, this.dataBuffer);
this.socket.write(message.buffer());
if (message) {
this.emit(message.command, message);
this._readMessage();
}
};
/**
@ -266,21 +188,4 @@ Peer.prototype._getSocket = function() {
return new Net.Socket();
};
// TODO: Remove this PATCH (yemel)
Buffers.prototype.skip = function (i) {
if (i == 0) return;
if (i == this.length) {
this.buffers = [];
this.length = 0;
return;
}
var pos = this.pos(i);
this.buffers = this.buffers.slice(pos.buf);
this.buffers[0] = new Buffer(this.buffers[0].slice(pos.offset));
this.length -= i;
};
module.exports = Peer;

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